From the junction with the UP (ex-SP) Tehachapi Pass line under the Route 14 bridge at South Mojave (MP 814.7), the line to Barstow swings away east across the Mojave Desert, a single-track line, CTC-controlled all the way, with frequent passing sidings near the western end, fewer on the eastern part of the line. All sidings on this line are to the south side of the main track in each case. The western end of the line runs through sheep grazing country with large herds of sheep tended by shepherds of Basque extraction (even though to the untrained eye the desert appears to be bereft of edible forage).
The line’s direction is initially just south of due east, across the desert floor. There is a detector at MP 813.0, with intermediate signals just a few feet further east (but numbered 812.1/2). The west end of Sanborn siding is at MP 811.0, with a pair of searchlight signals on one pole facing west, controlling entry to the main/siding, and two individual searchlight signals facing east controlling exit from the parallel tracks. The station sign for Sanborn is on the north side of the line at MP 810.1, as the line climbs over a saddle in a low ridge and angles to just north of due east. The east end of Sanborn siding is at MP 809.2, and is provided with a set of signals that mirrors those at the west end of the siding. There is a bridge over an arroyo not far east of the east end of the siding.
There are intermediate signals just east of MP 808, numbered 807.1/2, and intermediate signals just east of MP 806 numbered 805.1/2. There is an ungated road crossing just east of those signals. The west end of Bissell siding is at MP 804.4, with the same signal complement as at Sanborn, there is a double-ended spur off the south track at Bissell, provided with derails at both ends. The line now enters the northwest corner of Edwards Air Force Base, passing through a ridge in a lengthy cut as it heads east-northeast on a segment of line built in the early 1950s (the date 1953 is cast into the Rosamond Boulevard overpass at Edwards) to replace the original line that ran further south on land that became Edwards AFB after WWII, and the east end of Bissell is in the cut at MP 802.7, also provided with the same signal complement as at Sanborn. There are intermediate signals at MP 801.1/2, in the cut and 799.1/2 on an embankment, with the line now heading due east, and a culvert at MP 799.8 between them.
The west end of Edwards siding is on that embankment at MP 798.0, with the usual complement of signals. The station sign for Edwards is on the north side of the line at MP 797.1, adjacent to a BNSF Maintenance-of-Way depot, with a locomotive spur on the south side of the line, in between the east and west legs of a wye that connects to a track south to some fuel tanks about four miles south in Edwards AFB. Immediately east of the maintenance base is the concrete bridge over Rosamond Boulevard, the north entrance to the AFB, with the east end of Edwards siding a little way further east, with the usual complement of signals. There is a bridge over an arroyo and intermediate signals at MP 794.1/2, both directly south of the south end of Clay Mine Road. The west end of Silt siding is at MP 790.5, with the usual complement of signals, after which Twenty Mule Team Road comes alongside from the north and parallels the line on the north side all the way east through Boron.
There is a bridge over an arroyo near the station sign for Silt (MP 789.6), and the east end of Silt is at MP 788.8. Rocket Site Road ( an entrance to a separate part of Edwards AFB) crosses the line at MP 788.3, and there are intermediate signals at MP 786.2, east of the south end of Borax Road, Boron. Del Oro Street, Boron, crosses the line at grade, and the west end of Boron siding is at MP 784.9, with the usual set of signals. The mine spur to the borax mine north of Boron (along Borax Road) departs northwestward from the northerly track at the west end of Boron siding, crosses over Twenty Mule Team Road at grade, and passes under Route 58 with a concrete bridge, a little way to the northwest. There is a grade crossing on the main line at Boron Road, MP 783.9, and the east end of Boron siding is at MP 783.1, also with the usual signals.
There are intermediate signals at MP 781.1/2, Route 58 crosses the line at grade from the northwest to the southeast, there is a bridge over an arroyo and intermediate signals at MP 778.1/2. At MP 777.7, the line crosses over US 395 just north of the small community of Kramer Junction, aka Four Corners (intersection of US 395 and California 58). There is a bridge over a wash between MP 776 and 777, intermediate signals at MP 775.1/2, and another bridge over a wash at MP 775.7. The west end of Jim Grey siding is at MP 773.8, with the usual array of west facing and east facing signals. There is a bridge over a wash at MP 773.2, and the Jim Grey station sign at MP 773.0, followed by a short spur off the south track of the siding. The east end of Jim Grey is at MP 772.1, also with the usual array of signals.
There is a bridge over a wash at MP 770.7, intermediate signals at MP 769.1/2 and at MP 766.1/2, a bridge over a wash at MP 765.1 and a detector at MP 765.0. Harper Lake Road crosses at grade at MP 764.6, there are more intermediate signals at MP 763.1/2 and 760.1/2, the west end of Hinkley, with the usual complement of signals, is at MP 758.0, and the station sign Hinkley at MP 757.2. There is a road crossing at Almeda Street, Hinkley, at MP 757.1, the west facing signals at the east end of Hinkley, Hinkley Road grade crossing, the siding switch and the east facing signals at the east end of Hinkley (in that order), all at MP 756.4.
There are intermediate signals at MP 754.1/2, and a grade crossing at Lenwood Road at MP 752.2, where the line comes alongside Route 58 again, more intermediate signals?? at Waterman, MP 751.3?? as the line turns from eastward to south-southeastward and the speed limit drops from the 70 mph it has been all the way from South Mojave to 60 mph, a through girder bridge over Community Road, Waterman/Barstow, a lengthy concrete bridge over the Mojave River, and the various switches and signals at Hutt, MP 749A.9, where the speed limit drops to 50 mph and the line splits into the north and south legs of the wye at Valley Junction, MP 749A.8, where the speed limit drops to 40 mph and the line joins the Cajon Subdivision and/or enters the west end of Barstow Yard on the dual-level wye on the east side of Route 58 as the latter heads for its junction with I-15.